Merge pull request #9304 from hashicorp/b-legacy-executors-are-executors

Legacy executors are executors after all

CHANGELOG.md

@@ -43,6 +43,7 @@ BUG FIXES:
  * config (Enterprise): Fixed default enterprise config merging. [[GH-9083](https://github.com/hashicorp/nomad/pull/9083)]
  * client: Fixed an issue with the Java fingerprinter on macOS causing pop-up notifications when no JVM installed. [[GH-9225](https://github.com/hashicorp/nomad/pull/9225)] 
  * client: Fixed an fingerprinter issue detecting bridge kernel module [[GH-9299](https://github.com/hashicorp/nomad/pull/9299)]
+ * client: Fixed an in-place upgrade bug, where a Nomad client may fail to manage tasks that were started with pre-0.9 Nomad client. [[GH-9304](https://github.com/hashicorp/nomad/pull/9304)]
  * consul: Fixed a bug to correctly validate task when using script-checks in group-level services [[GH-8952](https://github.com/hashicorp/nomad/issues/8952)]
  * consul: Fixed a bug where canary_meta was not being interpolated with environment variables [[GH-9096](https://github.com/hashicorp/nomad/pull/9096)]
  * consul/connect: Fixed a bug to correctly trigger updates on jobspec changes [[GH-9029](https://github.com/hashicorp/nomad/pull/9029)]

drivers/shared/executor/legacy_executor_wrapper.go

@@ -36,6 +36,9 @@ type legacyExecutorWrapper struct {
 	logger hclog.Logger
 }
 
+// validate that legacyExecutorWrapper is an executor
+var _ Executor = (*legacyExecutorWrapper)(nil)
+
 func (l *legacyExecutorWrapper) Launch(launchCmd *ExecCommand) (*ProcessState, error) {
 	return nil, fmt.Errorf("operation not supported for legacy exec wrapper")
 }
@@ -133,6 +136,11 @@ func (l *legacyExecutorWrapper) Exec(deadline time.Time, cmd string, args []stri
 	return l.client.Exec(deadline, cmd, args)
 }
 
+func (l *legacyExecutorWrapper) ExecStreaming(ctx context.Context, cmd []string, tty bool,
+	stream drivers.ExecTaskStream) error {
+	return fmt.Errorf("operation not supported for legacy exec wrapper")
+}
+
 type pre09ExecutorRPC struct {
 	client *rpc.Client
 	logger hclog.Logger